Tooth cleaning device and a method for indicating the cleaning duration

ABSTRACT

The invention relates to an electric tooth cleaning device and to a method for automatically indicating the cleaning duration when cleaning teeth, whereby a timer signal is emitted using a time element after the termination of a set cleaning duration in a tooth cleaning session. According to the invention, the set cleaning duration, whose termination prompts the emission of a timer signal, is modified. An actual cleaning duration in the tooth cleaning session is registered by a time registration device. The deviation of the actual cleaning duration from a predetermined standard cleaning duration is determined by means of an evaluation device. The set cleaning duration of a subsequent tooth cleaning session is then defined depending on the deviation that has been determined.

[0001] The present invention relates to a method for indicating the cleaning time in teeth cleaning, in which after termination of a target cleaning time of a tooth cleaning process, a timer-signal is emitted. The invention further relates to an electrical tooth cleaning device, in particular, its tooth brushes, with a timing member for production of a signal after termination of a target cleaning time of a tooth cleaning process.

[0002] It is known with electric tooth brushes to provide a time switch, which starting from switching-on of the electric tooth brush, emits a discernible signal after a predetermined time duration for a user. The signals serve to indicate to the use the end of the cleaning time. With the signals, acoustic or optical signals can operate, which the user is made aware of at the end of the optimal cleaning time. From WO 96/14025, it is known to not emit an acoustic or optical timer signal, rather instead to switch the drive motor of the tooth brush on and off rapidly so that the drive motor stutters. This can be done by the user directly in the hand or in the mouth.

[0003] In addition, it can be provided that the electric tooth brush is switched off after termination of the target cleaning time automatically. This is inexpedient if the timer-signal merely indicates that a partial region of the teeth, such as, for example, a biting quadrant, as been completely cleaned. In WO 97/19650, it therefore proposed to switch again to regular cleaning operation after the stuttered operation, so that the biting quadrant can be cleaned completely according to the desire of the user. As soon as the user changes to another biting quadrant, he can start anew the timing member by means of a button, in order again to be provided the target cleaning time for this new biting quadrant. This method for indicating the target cleaning time does not fulfill the wishes of all tooth brush users, however.

[0004] From DE 197 28 964 A1, a tooth brush with a device is known, which signals to the tooth brush user the beginning and end of the optimal tooth cleaning time. On the tooth brush, a knob or slide switch is mounted, with which at the beginning of the teeth cleaning, an acoustic signal can be released, which is repeated automatically after approximately three minutes. In addition, a signal after approximately three months of using the tooth brush can be emitted, whereby the user is informed that the tooth brush should be replaced with a new tooth brush.

[0005] U.S. Pat. No. 6,029,303 discloses a manual tooth brush with an electric circuit, which emits a discernible signal regarding the cleaning time. The beginning of the cleaning time can be determined, for example, by means of a movement sensor, which releases a timing member, whereby then at the end of the time, a signal discernible by the user is emitted from the timing member of an electrical circuit. Also, the possibility exists that with the electronic circuit, the entire cleaning time is added up and a further signal from the electronic circuit is then emitted, which falls below the recommended use time of the tooth brush.

[0006] The present invention is based on the object of producing an improved tooth cleaning device as well as an improved method of the above-disclosed type, in which along with deviation of the actual cleaning time from the predetermined target cleaning time in an individual case, however, over multiple, separately successive cleaning processes, a mean value for the actual cleaning time can be reached.

[0007] This object is solved by a method according to claim 1. The above-noted object is further resolved by a tooth cleaning device according to claim 12. Preferred embodiments of the invention are the subject matter of the dependent claims.

[0008] According to he present invention, the target cleaning time is variably determined, in particular, then, when predetermined cleaning times are not obtained from the user. An actual cleaning time of the tooth cleaning process is determined by means of a time determination device. By means of an evaluation device, the deviation of the determined actual cleaning time from a predetermined, likewise constant or also variable standard cleaning time depending on parameters, is determined. By means of a control device, the target time, after whose termination the timer-signal is emitted, for a later tooth cleaning process in dependence of the determined deviation, is determined anew. The target cleaning time can be adapted personally to the cleaning environment and/or for example, to the daily rhythm of the user. Behind the variable timer-signal, the consideration exists that also a combination of short and longer cleaning processes resulting from the variable timer-signal can run in the middle of a good or satisfactory cleaning result, since a cleaning process that was too short is compensated by a lengthened cleaning time with the next or subsequently later cleaning process. The likewise variable standard cleaning time can adopt different values that are user-specific, for example, for children or adults, and/or cleaning-tool specific, for example, depending on the type of implement use, such as a flat brush, inter-dental brush, floss offset or the like.

[0009] In a further embodiment of the invention, a cleaning time account is managed, which takes into consideration the deviations of the actual cleaning time from the predetermined standard cleaning time with multiple, previous tooth cleaning processes, which determines the sum of multiple tooth cleaning processes. A cleaning time memory can be provided, which stores the sum of deviations between the actual cleaning time and the standard cleaning time determined from multiple tooth cleaning processes. The control device uses the cleaning time memory with the determination of the target cleaning time for a new tooth cleaning process, then, and determines the target cleaning time in dependence on the determined deviations with one or more previous cleaning processes. With multiple deviations, correspondingly marked changes of the target cleaning time take place or with converse deviations, also weaker changes of the target cleaning time take place. In particular, the target cleaning time relative to the standard cleaning time is markedly lengthened when only one shortened tooth cleaning process was performed.

[0010] Preferably, the deviations between actual cleaning time and standard cleaning time only up to a predetermined amount are taken into consideration. In particular, the deviations between the actual cleaning times and the standard cleaning times can be added up only to a known capping limit and can be stored in the cleaning time memory. Upon exceeding the capping limit, the threshold value can be taken into consideration or the target time change can be considered.

[0011] It is likewise possible not only to limit the sum of the deviations, but also to provide a capping limit for the individual deviations. If the actual cleaning time deviations to intensely from the predetermined standard cleaning time, only the provided maximum amount of the deviation is considered for the change of the target cleaning time of the next tooth cleaning process. Such a limitation of the considered deviations is based on the conclusion that a comparison of different tooth cleaning process is possible only if a known frame and optimal tooth cleanliness cannot be achieved, when the fluctuations are too marked. Thus, only a change of the target cleaning time occurs in a known range.

[0012] In particular, it can likewise be provided that the control device determines the target cleaning time always within a predetermined range. This range basically can be formed differently. Thus, in particular, a maximum lengthening of the target cleaning time can be provided.

[0013] The range limit for the target cleaning time can be determined differently. According to an advantageous form of the invention, the standard cleaning time can be provided as the minimal target cleaning time. The control device determines the target cleaning time always as greater or the same as the standard cleaning time. When the user positively fills up his cleaning time ledger by too long of a tooth cleaning over the target cleaning time, the timer, however, is not activated before the standard cleaning time by the control device during the next tooth cleaning process.

[0014] According to an alternative embodiment of the invention, it can be provided that the target cleaning time can not only be lengthened, but also shortened relative to the standard cleaning time. For the cleaning time account, then, also cleaning times over the target cleaning time are taken into consideration and referenced for the determination of the next target cleaning time. If the user, for example, cleans his teeth in the evening for a particularly long time over the standard cleaning time, a corresponding credit is placed on the cleaning time account and the target cleaning time on the next morning is corresponding shortened, likewise, also below the normal standard cleaning time.

[0015] The deviations determined with a previous cleaning process or with multiple previous cleaning processes can be taken into consideration in various ways with the determination of the target cleaning time. Thus, basically it can be provided that the deviations are passed along only in part with the change of the target cleaning time. For example, a cleaning time that last 30 seconds over the standard cleaning time can lead to only a 15-second shortening of the next target cleaning time. According to, an advantageous embodiment of the invention, the determined deviation or the sum of the determined deviations between actual cleaning times and standard cleaning times is directly abstracted, that is, a one-to-one determination of the target time to the standard cleaning time is proposed or abstracted. This takes place preferably only within the determined limits, so that the target cleaning time is changed always within the predetermined capping limits.

[0016] In a further embodiment of the invention, only tooth cleaning processes are taken into consideration for the cleaning time account, which correspond to the determined minimum specifications, in particular, that last longer than a minimum time. If the actual cleaning time of a tooth cleaning process lies below the minimum limit, which are determined by different, for example, user- or cleaning-tool-specific factors, and for example, and can amount to 30 seconds, no deviation between the actual cleaning time and the standard cleaning time is determined or this is not taken into consideration with the determination of the target cleaning time of a later tooth cleaning process.

[0017] In order to better signify to the user of the tooth cleaning device the adaptation of the time or his deviation from the standard cleaning time, it can preferably be provided that with a target cleaning time that is changed, preferably lengthened relative to the standard cleaning time, already for beginning of the respective, tooth cleaning process, a corresponding warning signal is emitted, which indicates to the user that the last tooth cleaning process was too short and this time, a correspondingly longer target cleaning time is necessary.

[0018] In addition, in a further embodiment of the present invention, it can be provided that upon termination of a tooth cleaning process before reaching the standard cleaning time, a warning signal is emitted, which indicates to the user that he cleaned his teeth for too short of a time. It also can be preferably provided that a further warning signal is provided, when the tooth cleaning process is interrupted before reaching the respectively variable target cleaning time. Accordingly, the noted warning signals are different from one another, so that it is clear which change or deviation is made or occurred.

[0019] In order to achieve a measured determination and evaluation of the actual cleaning times, a coast down timer can be provided. With the determination of the actual cleaning time, temporary interruptions of the tooth cleaning process can be ignored. This can be particularly sensible with a temporary on/off switching of the tooth cleaning device, for example, upon changing from one biting quadrant to the next biting quadrant or, for example, when tooth paste is removed from the mouth and the tooth brush is turned off temporarily. If the time determination and the corresponding evaluation were run anew each time, instead, few sensible results would be achieved.

[0020] Next, the invention will be described in more detail with reference to a preferred embodiment and associated drawings. In the drawings:

[0021]FIG. 1 shows a schematic representation of an electric tooth brush according to the present invention;

[0022]FIG. 2 is a block diagram of a variable timing member of the electric tooth brush according to FIG. 1; and

[0023]FIG. 3 is a flow diagram of the variable timing member, which makes clear the changes of a cleaning time account over multiple cleaning processes.

[0024] In FIG. 1, an electric tooth brush 1 is shown, in which in a housing 2, an accumulator 3, a motor 4, and a drive 5 are accommodated. On a free end of the electric tooth brush 1, an attachment brush 6 can be inserted, which has a rotary-supported stiff-bristled support 7 with bristles 8 attached thereto. The bristle-support 7 can be rotary driven in an oscillating manner about a rotational axis that is essentially perpendicular to the longitudinal axis of the attachment brush 6 in a known manner by the motor 4.

[0025] In the housing 2 of the tooth brush 1, in addition, a coil 9 as well as control device 10 in the form of a circuit board are accommodated. The coil 9 is arranged on the end of the housing 2 lying opposite the attachment brush 6 and serves for charging the accumulator 3. The control device 10 includes various electronic components, which control the operation of the electric tooth brush 1. Accessible from outside, a switch 11 is arranged in the wall of the housing 2, with which the motor 4 of the tooth brush can be switched on and off. To this purpose, an output unit 12 is arranged in the wall of the housing 2, which is connected with the control unit 10 and serves to emit signals, in particular, the timer signal, for indicating the termination of the target cleaning time. The output unit 12 can be variously formed, for example, optically or acoustically. Also, other output of the signals can be provided. For example, the motor 11 can be placed into a stuttering operation, such as described in WO 97/19650. Regarding the structure of the timer-signal in this connection, specific reference is made to WO 97/19650.

[0026] The control device 10 includes, in particular, a timing member or a timer for production of a timer-signal after termination of a target cleaning time. Such a timer is shown in FIG. 2 and is generally designated with reference numeral 13. In a memory 14, first cleaning constants are stored, which determined the boundary conditions of the target cleaning process. In particular, a standard cleaning time and a minimum cleaning time for an effectual cleaning process can be stored in the memory.

[0027] In addition, a time determination device 15 is provided, which can be activated by a switch 11 for switching on the motor 4. Preferably, it includes a coasting down means, so that with temporary interruptions of the motor operation, it continues to run. It determines the time between switching on of the motor 4 and its definite switching off. A central component of the timer or the timing member for emitting the timer signal is the evaluation device 16, which has access to the memory 14 and which is connected with the time determination device 15, in order to obtain the actual cleaning time. It determines the deviation of the respectively determined actual cleaning times from the standard cleaning times stored in the memory 14. It places the determined deviations on a cleaning time account MPK, and determines with reference to the deviations from previous tooth cleaning process the target cleaning time, after whose termination a timer-signal is emitted. The memory 14 and the cleaning time account MPK can be formed from separate storage components, as shown in the drawing. Alternatively, however, they can also be formed as a common memory. For outputting the timer signal, the evaluation device 16 is connected with the output unit 12. For one, this can emit a timer-signal 17, which indicates the termination of the variably determined target cleaning time. In addition, they can emit different warning signals 18, which indicate to the user different deviations or changes of the time switch. In particular, a first warning signal W1 can be emitted, when a cleaning process is discontinued under the minimum cleaning time. A second warning signal W2 can be emitted, when the user switches of the apparatus before reaching the timer-signal 17. The warning signal W2 preferably can be distinguished from the first warning signal W1. Finally, in order to note a changed target cleaning time, relative to the standard cleaning time, with the next cleaning process , a third warning signal W3 or advisory signal can be emitted, which is distinguishable from the previous signals and indicates to the user that the timer-time was changed. The named signals can be emitted optically or acoustically. Also, the previously described stuttered-motor can be provided. Other signal output forms are possible.

[0028] Next, the function of the tooth brush 1 and in particular, the timing member 13, will be explained in greater detail with references to different cleaning processes in connection with FIG. 3.

[0029] First, the cleaning time account MPK guided by the evaluation device 16 is empty. For the cleaning time account, a capping limit of 90 seconds is, provided, that is, deviations between actual cleaning time and standard cleaning time up to merely a total of 90 seconds can be added up. The cleaning time account has a capacity of 90 seconds. The standard cleaning time stored in the memory 14 amounts to 120 seconds in the shown embodiment. The minimum cleaning time likewise stored in the memory 14 for an effectual cleaning process is determined with 30 seconds.

[0030] With a first cleaning process, the user terminates his cleaning process after 15 seconds, without waiting for a signal from the timing member 13. The first warning signal W1 indicates that the cleaning process was too short and is not valued for the time balance. Accordingly, the cleaning time account remains empty.

[0031] With a second cleaning process, the user terminates his cleaning process after 105 seconds, likewise, again without emission of the timer-signal. The warning signal W2 indicates that the recommended standard cleaning time has not been reached. The evaluation device 16 determines the deviation between the actual cleaning time and the stored standard cleaning time. The difference of 105 seconds and 120 seconds, namely, 15 seconds less time, is added to the cleaning time account. The cleaning time account obtains therewith the value of 15 seconds less time.

[0032] With a third cleaning process, the timer is reconfigured. The target cleaning time is placed to a value differing from the standard cleaning time. The target cleaning time is set up to the sum of the standard time of 120 seconds and the stored value of 15 seconds, namely, to 135 seconds. In order to make noticeable the now-lengthened cleaning time, this third warning signal W3 sounds directly after the switching on of the tooth brush, in order to indicate to the user that a lengthened target cleaning time is to be obtained. The user, however, terminates his cleaning after 90 seconds without the timer-signal. The second warning signal W2 sounds. The evaluation device 16 determines anew a less time of 30 seconds. This deviation is added to the previously determined deviation, so that the cleaning account is set at a value of 45 seconds.

[0033] With a fourth cleaning process, first the timer is adjusted corresponding to the deviations stored in the cleaning time account. On the standard cleaning time of 120 seconds, the the sum of the deviations of 45 seconds stored in the cleaning time account is added, so that the target cleaning time is adjusted to 165 seconds. With switching on, the warning signal W3 sounds, which provides the lengthened target cleaning time. The user terminates his cleaning process this time after 135 seconds without the timer-signals. The warning signal W2 sounds anew. This time, however, the value of the cleaning time account is reduced, since the cleaning process lasted longer than the standard cleaning time of 120 seconds. The less-cleaning time is reduced by the difference of 135 seconds to the standard cleaning time of 120 seconds. In the cleaning time account, a less time of now 30 seconds is stored.

[0034] With a fifth cleaning process, the target cleaning time corresponding to the less time of 30 seconds is set to 150 seconds, which corresponds to the sum of the standard cleaning time and the stored less cleaning time. Upon switching on, signal W3 sounds anew. The user terminates his cleaning process, however, after 45 seconds without the timer-signal, so that the second warning signal W2 sounds anew. The evaluation, device 16 determines a deviation of 75 seconds to the standard cleaning time of 120 seconds. Accordingly, the cleaning time account must be set to a less time of 105 seconds. Since, however, a capping limit of 90 seconds for the cleaning time account is provided, the threshold value of the less time of 90 seconds is stored in the cleaning time account.

[0035] According to the maximum less time of 90 seconds, which is stored in the cleaning time account MPK, the target cleaning time and, accordingly, the timer 13 is set to the sum of the standard cleaning time of 120 seconds and the maximum less cleaning time of 90 seconds, that is, to 210 seconds. Upon switching on the tooth brush, the warning signal W3 sounds anew. The user cleans for the set timer time and after 210 seconds, the timer signal 17 is emitted from the output unit 12. Since the target cleaning time would be completely processed, the cleaning time account is reset. The stored less time amounts now to 0 seconds.

[0036] In a seventh and last cleaning process according to the illustration, the timer is set to the standard duration of 120 seconds, since in the cleaning time account, no miss-out times are stored. This time, no warning signal sounds upon switching on of the tooth brush. The user cleans until the timer signal, which is emitted after 120 seconds and than for another 30 seconds until to a total cleaning time of 150 seconds. In the shown embodiment, the actual cleaning times over the target cleaning time are not assessed, that is, the cleaning time account is set upon reaching the target cleaning time merely to 0. This was provided in the present case, so that the value of the cleaning time account MPF remains at 0 seconds. 

1. A method for specifying the cleaning time in teeth brushing, in which after termination of a target cleaning time of a tooth cleaning process, a timer-signal (17) is emitted, characterized in that an actual cleaning time of the tooth cleaning is detected, whose deviation from a predetermined standard cleaning time is determined and the target cleaning time of a later tooth cleaning process is determined in dependence on the determined deviation.
 2. The method according to claim 1, characterized in that the deviations between actual cleaning time and standard cleaning time are added up over multiple cleaning time processes and saved on a cleaning time account (MPK), as well as the target cleaning time of the respective tooth cleaning process in dependence on the actual status of the cleaning time account.
 3. The method according to one of the preceding claims, characterized in that the deviations between actual cleaning time and standard cleaning time duration are taken into consideration only up to a predetermined amount.
 4. The method according to one of the preceding claims, characterized in that the target cleaning time is determined always within a predetermined range.
 5. The method according to one of the preceding claims, characterized in that the target cleaning time is determined to be always greater or the same as the standard cleaning time.
 6. The method according to one of claims 1 through 4, characterized in that the cleaning time is determined to be smaller than the standard cleaning time.
 7. The method according to one of the preceding claims, characterized in that for determination of the target cleaning, time, the standard cleaning time is lengthened or shortened to the previously determined deviation or to the sum of the previously determined deviations between standard cleaning time and actual cleaning time.
 8. The method according to one of the preceding claims, characterized in that a deviation between the actual cleaning time and the standard cleaning time is only determined when the actual cleaning time of a tooth cleaning process lies above a predetermined minimum cleaning time.
 9. Method according to one of the preceding claims, characterized in that with a target cleaning time that has been changed, in particular, lengthened, relative to the standard cleaning time, at the beginning of the respective tooth brushing process, a warning signal (W3) is emitted.
 10. The method according to one of the preceding claims, characterized in that with termination of a tooth cleaning process before reaching the standard cleaning time and/or the target cleaning time and/or the minimum cleaning time, a warning signal (W1, W2) is emitted.
 11. The method according to one of the preceding claims, characterized in that with the determination of the actual cleaning time, temporary interruptions of the tooth cleaning process are ignored.
 12. An electric teeth cleaning device, in particular, tooth brushes, with a timing member (13) for production of a signal after termination of a target cleaning time of a tooth cleaning process, characterized in that a time recording device (15) for determination of an actual cleaning time of the tooth cleaning process, an evaluation unit (16) for determination of a deviation of the determined actual cleaning time of a predetermined standard cleaning time, as well as a control device (10) for changing the target time in dependence on the determined deviation are provided.
 13. The tooth cleaning device according to claim 12, characterized in that a cleaning time memory (14) for storage of a sum of deviations determined over multiple tooth cleaning processes between the respective actual cleaning time and the standard cleaning time is provided, and the control device (10) is formed, such that the target time of the respective tooth cleaning process is determined in dependence on the storage sum of the determined deviations.
 14. The tooth cleaning device according to one of the preceding claims 12 or 13, characterized in that a limiting device for limiting the sum of the deviations, which is stored in the cleaning time memory (14), is provided.
 15. The tooth cleaning device according to one of the preceding claims 12 to 14, characterized in that the target cleaning time limits are stored in the cleaning time memory (14) and the control device is formed, such that the target cleaning time is determined always within the stored limits.
 16. The tooth cleaning device according to one of the preceding claims 12 through 15, characterized in that the control device is formed, such that the target cleaning time is always determined to be greater or the same as the standard cleaning time.
 17. The tooth cleaning device according to one of claims 12 through 15, characterized in that the control device is formed, such that the target cleaning time is determined to be smaller than the standard cleaning time.
 18. The tooth cleaning device according to one of the preceding claims 12 through 17, characterized in that the control device has a summation device for adding up the standard cleaning time and the previously determined deviation or the sum of the previously determined deviations, and the control device is formed, such that it determines the sum from the standard cleaning time and the stored deviations as the target cleaning time.
 19. The tooth cleaning device according to one of the preceding claims 12 through 18, characterized in that a minimum cleaning time member is provided, that upon falling short of a minimum cleaning time, consideration of the deviation between the actual cleaning time and the standard cleaning time for determination of the target cleaning time is eliminated.
 20. The tooth cleaning device according to one of the preceding claims 12 through 19, characterized in that a warning signal device for output of a warning signal (W3) is provided with a changed target cleaning time, in particular, a lengthened target cleaning time relative to the standard cleaning time at the beginning the respective tooth cleaning process.
 21. The tooth cleaning device according to one of the preceding claims 12 through 20, characterized in that a warning signal device for output of a warning signal (W1, W2) upon termination of a tooth cleaning process before reaching the standard cleaning time and/or the target cleaning time and/or the minimum cleaning time is provided.
 22. The tooth cleaning device according to one of the preceding claims 12 through 21, characterized in that the time determination device (15) has a coast down member for determination of the actual cleaning time via temporary interruption of the tooth cleaning process. 